Optical proximity correction (OPC) methodology employing multiple OPC programs

摘要

A marker layer is placed in regions of a design layout in which an image slope is less than a critical image slope or a perimeter to area ratio is less than a critical perimeter to area ratio. Multiple optical proximity correction (OPC) can be generated by grouping subsets of process conditions at which error mean and/or error root-mean-square (RMS) exceed threshold values. Regions marked with the marker layer are processed with a rigorous OPC employing at least one non-standard resist model, while unmarked regions of the layout are processes with a standard OPC program that is less rigorous than the at least one non-standard resist model. Additionally, number of edges and areal image contrast can be compared among layout clips to determine threshold values for the number of edges and the areal image contrast, which can be employed to determine if multiple OPC is needed for each layout clip.